Locomotive throttle valve



June 17, 1930. F T N 1,764,366

LOCOMOTIVE THROTTLE VALVE Filed May 5, 1927 2 Sheets-Sheet l 37; IF'IGJ' W\TNESSES aZ KZ J NTR J June 17, 1930. sTUEBlNG 7 1,764,366

LOCOMOTIVE THROTTLE VALVE Filed May 5, 1927 2 Shoots-Sheet 2 WITNESSESPatented June 17, 1930 UNITED STATES PATENT OFFICE ALBERT I. STUEBING,OI SCLBSDALE, NEW YORK Looono'rrvn rrmomn VALVE.

Application am m 5, 1921. Serial No. 189,101.

The object of my invention is to provide a throttle valve of the singlepoppet type, which Fig. 3, a transverse section on the line C C of Fig.1 and; Fig. 4, a vertical transverse section through the main throttlevalve member, on the line D D of Fig. 2.

In the practice of my invention, referring descriptively to the specificembodiment 29 thereof which is herein exemplified, the main throttlevalve member, 1, is of the single seated poppet type, and isofcylindricalform,

with a body of reduced diameter, and a coni-- cal face, 1, surroundingits bottom,- which face is adapted to be seated upon a similarly boredface on a seat ring, 2, fitted in an opening in a wall, 3, which extendsacross a throttle valve chamber or chest, 3, and is interposed between asteam supply inlet, 3, and a steam delivery outlet, 3', on said chest.The valve chest is cast with both of its ends open, to permit of theinsertion, and removal, when required, of the operative mechanism, and,for operating, the upper end of the chest is closed by a cap plate, 3,and the lower end by a similar plate, 3", secured in place by bolts, 3,and

nuts, 3". The throttle valve is fitted freely on a stem, 1", so as to becapable of movement axially, relatively thereto, and controlscommunicationfor. steam; through the chest, 3, from the inlet, 3, to theoutlet, 3", thereof, from which it is delivered to the steamdistribution valves of the locomotive on which the appliance is locatedA balancing chamber, 3, corresponding in diameter with the throttlevalve, is forme in a cylindrical block, 3", fixed in the valve chest, 3,above, and in line axiallly; with, the main throttle valve member, 1, te body of which is finished to fit truly, and traverse,

ably axially, in the block, 3". Said block is secured in position bybolts, 3, passing through a circumferential flange on its top, whichbears on the top of the valve chest, and through the cap plate, 3*,which closes the top of the balancing chamber, and the upper end of thevalve chest. The bolts, 3, are tapped into the top of the valve chest,and are engaged by nuts, 3, which hold the cap plate, 3, removinposition.

differential pressure area balancing piston, 7, is secured to the mainthrottle valve.

member, 1, by bolts, 7*, and nuts, 7, and 'is- Y fitted trul 1n thebalancing chamber, 3", which it' 'vides into. an upper balancingcompartment, and a lower cushioning compartnient, and in which it isadapted to traverse with the main valve, in the unseating and seatingmovements thereof. The iston, Z, is of T section, its top portion, whichfits the chamber, corresponding substantially in diameter with theseatin face, 1, of the main valve, 1, and its depending bottom-portionfitting against,'and corresponding in diameter with, the body of saidvalve. The piston is so located in the balancing chamber,-.that a lowercushioning compartment, in the form of an annular space, shall bepresented therein, around its bottom portion, and it is rendereddifferential in pressure areas, by reason of its upper portion beingsubject, on its top, to pressure throughout its entire area, and, on itsbottom, to pressure'only throughout the transverse sectional area of theannular space between its lower portion and the bore of the balancingchamber. Said space communicates with the inlet passage, 3, by a releaseport, 7. h

The valve stem, lflfigsses freely through, and is guided in; a cy dricalopening in a bar, 1 extending across the main valve, 1, adjoining itsseating face, and carries, adjacent to the top of the body of saidvalve, 21 balancing valve, 8, having a conical upper face, 8 adapted toseat on a corresponding face at the bottom of a passage, which extendsthrough the balancing piston, 7. The balancing valve, 8, is alsoprovided witha conical lower face, 8", adapted toseat on a similar faceat the top of a passage, 1, in the main ancing piston, leading from theconical valve seat at the bottom of the passage, 7 into the space in thebalancing chamber below the balancing piston, and a port, 7 is alsoformed therein, leading from said space to a port, 1,

extending through the body of the main valve, and opening into theinlet, 3. Ports, 7 extend vertically through the balancing piston, 7,from the upper face thereof, into the space around the upper face of thebalancing valve, as shown in Fig. 4, and a by-pass port, 7, (one ormore) may be formed in said piston, to establish communication betweenits opposite sides.

The valve stem, 1", is threaded at, and adjoining, its lower end, toengage a jaw, 1, and a lock nut, 1, bearing thereon, and may also besecured to the jaw by a key, 1. The jaw is coupled, b a lifting link, 9,and crank arm, 10, to a sha t, 11, passing through a stufling box in thevalve chest, 3, and carrying, at its outer end a lever arm, 12, bymovement of which the balancing valve, 8, may be raised and lowered, asrequired for the unseating v and seating of the main throttle valve, 1.

In the operation of the appliance, when it is desired to unseat the.main throttle valve, which is continuously subject to steam pressuredownwardly, and is normally unbalanced, equilibrium of pressure, on itsopposite sides, is established by the upward movement of the pilotvalve, 8, through the lever arm, 12, and its described connections, suchmovement effecting the seating of the upper face, 8. of the pilot valveon the balancing piston, 7

During the periods that the main valve is seated, steam from the inlet,3, passes through the port 1 the adjoining balancing piston port, 7 andthe port, 7 into the compartment of the balancing chamber, 3, above thebalancing piston 7. Steam enters the compartment of the chamber, belowthe piston, through the port 7. Steam from the compartment below thepiston, may alsoenter the compartment above the piston, through theports, 7, and 7*, and through the port 7 when the latter is provided.The piston is therefore subject to a preponderance of downward pressuretendin' to maintain the closure of the main valve. pon the seating ofthe pilot valve on the balancin piston, by its upward movement abovestate communication between the inlet passage,'3, and the compartment ofthe balancing chamber, 3, above the piston, is cut off, except to thelimited extent afforded by the port 7*, the cushioning chamber and theport, 7', when said port is provided, to permit at moderate preliminaryflow of steam to the cylinders before unseating the main valve. Thesteam in said compartment then escapes therefrom, through the pistonports, 7, which are always open and the middle passage in the mainvalve, which surrounds the valve stem, 1',, and passes into the deliveryinlet, 3". The pressures on the opposite sides of the main valve, 1, arethen, except as to the narrow annular area of the conical face of thevalve, equal in degree, and said valve being thus practically balanced,it maybe readily further raised from its seat, by continued movement ofthe lever arm, 12, to effect any desired degree of elevation of thevalve from its seat, for increasing steam delivery.

The main valve cannot be moved upward more rapidly than the steam flowsinto the annular compartment beneath the balancing piston through theport, 7*. Thus, by varying the size of this port, the maximum rate ofopening of the main valve can be regulated, and undesirable suddenadmission of steam to the cylinders is positively prevented. If it isdesirable to permit a moderate flow of steam to the cylinders before themain valve is raised, this can be provided throu h the application anduse of ports, 7. Port, should be larger than port, 7, so that when thepilot valve is raised, the pressure in the annular cavity under thebalancing piston is maintained substantially equal to that in the inlet,3.

The closure of the main valve is effected by moving the balancing valvedownward, by the actuating of the lever arm, 12, until itslowe'r face,8, seats in the main valve.

either through the port, 7", to the inlet, or

through the ports, 7", to the space above the piston in the balancingchamber. The outward flow of steam from the chamber is resultant uponthe differential of pressure. due to the force exerted by the pilotvalve and the excess of pressure above the piston relatively to thatbelow the main valve.

The closure of the main valve cannot occur more rapidly than thelowering of the pilot valve, as otherwise it would not be possible forthe lower face of the ilot valve to make contact with its seat on t emain valve, and the pressure above the piston would be released,balancing the upward and downward forces acting on the main valve. Evenif the pilot valve was held to its seat to follow a rapid movement ofthe main valve, it would be impossible for the latter to close morerapidly than the steam could be expelled from the annular space in thebalancing chamber,

cure by Letters Patenti 1. The combination of a throttle valve chest,having inlet and outlet passages; a

throttle valve, controlling communication between said passages; abalancing chamber; a differential pressure area piston, fittingin saidchamber, and dividing it into two compartments, said piston beingconnected to said valve; and means for balancing the throttle valve byreleasing pressure fromone of said compartments;

2. The combination of a throttle valve chest, having inlet and outletpassages; a throttle valve, controlling communication between saidpassages; a balancing chamber; a differential pressure area piston,fitting in said chamber and dividing it into two compartments, saidpiston being .connected to said valve; and amanually operable balancingvalve for releasing pressure from one of said compartments, to balancethe valve.

3. The combination of a throttle valve chest,.having inlet and outletpassages; a

; throttle valve, controlling communication between said passa 'es;..astem, on which the throttle valve is fitted, with the capacity ofrelative axial movement; a balancing chamber; a differentialpressurearea piston, fitted in said chamber, and dividing it intotwocompartments; and a balancing valve, fixed on the stem and controllingthe release of pressure from one of the compartments of said chamber, tobalance the valve.

4., The combination of a throttle valve chest, having inlet and outletpassages; a

throttle valve, controlling communication between said passagesandhaving a through steam passage communicating therewith; a stem, onwhich the throttle valveds fitted, with the capacity of relative axialmovement; a balancing chamber; a difierential pressurearea piston,fitted in said chamber; and a balancing valve, fixed on the stem andhaving a seating face, adapted to control communi cation between thebalancing chamber and the inlet passage of the valve chest, and anotherseating face, adapted to control communication between the balancingchamber and the through steam passage of the throttle valve. i

5. The combination of a throttle valve chest, having inlet and outletpassages; a throttle valve of the single poppet type, con trollingcommunication between said passages, said valve having a body of reduceddiameter, relatively to its seating face; a balancing chamber,corresponding substantially in diameter with the seating portion of thevalve; a difierential pressurearea piston, fitting in said chamber, saidpiston being spaced at a distance from the bottomof the balancingchamber, to provide an annular surrounding compartment, and means forbalancing the throttle valve by releasing pressure from the larger areaof the piston.

6. The combination of a throttle valve chest; having inlet and outletpassages; a throttle valve of the single poppet type, controllingcommunication between said passages, said valve having a body of reduceddiameter, relatively to its seating face; a

balancing chamber, corresponding substan tially in diameter with theseating portion of the valve; a differential pressure area'piston,

fitting in said chamber, and having a depending portion, correspondingin diameter with, and connected to, the body of the valve, said pistonbeing spaced at a distance from th bottom of the balancing chamber, toprovide an annular surrounding compartment; and means for balancing thethrottle valve b releasing pressure from the larger area of the piston.

*7; The combination of a throttle valve chest, having inlet. and outletpassages; a

throttle valve, controlling communication between said passages;a pistonchamber; a diflerential pressure area piston, fitting in said chamber,and dividing it into an upper balancing compartment and a lowercushioning compartment, said piston being connected to the throttlevalve; an inlet'port, establishing communication between the inletpassage and the balancing compartment; an outlet port, establishingcommunication between the balancing compartment and the outlet passage;a by-pass port, establishing communication between the balancingcompartment and the cushioning pompartment; and a valve controlling flowthrough said ports.

8. The combination of a throttle valve chest, having inlet .and outletpassages; a throttle valve, controlling communication between saidpassages; a piston chamber; a differentialpressure area piston, fittingin said chamber, and dividing it into an ;upper balancing compartmentand a lower cushioning compartment, sald piston being connected to v thethrottle valve; an inlet port, establisliin communication between theinlet passage and the balancing compartment; an outlet port,

establishing communication between the balancing compartment and theoutlet passage; a by-pass port, establishing communication between thebalancing compartment and the cushioning compartment a valve,controlling flow through said ports; and a port,restablishingcommunication between the inlet pas; sage and the cushioningcompartment.

9. The combination of a throttle valve chest having inlet and outletpassages; a throttle valve, controlling communication between saidpassages; a piston chamber: a differential pressure area piston, fittmgin said chamher, and dividing it into an upper balancing compartment anda lower cushioning compartment, said piston being connected to thethrottle valve; an inlet port, establishing communication between theinlet passage and the balancing compartment; an outlet port,

j establishing communication between the balancing compartment and theoutlet passage; a by-pass port, establishing communication between thebalancing compartment and the cushioning compartment; a valve,COIltIOllillg flow through said ports; a port, establishingcommunication between the inlet passage and the cushioning compartment;and a port, establishing communication between the cushioningcompartment and the balancing compartment.

fastened to the headed member being formed to provide a piston' 10. In athrottle valve, the combination of a casing having inlet and outletpassages; a valve controlling communication -between said passages; ahead detachably fastened to an end of the casing, a member detachablyend of the casing said chamber; a differential pressure area piston'fitting in said chamber, and dividing it into an upper balancingcompartment and a lower cushioning compartment, said piston beingconnected to the throttle valve;-an inlet port establishingcommunication between the inlet passage and the balancing compartment;an

outlet port, establishing communication between the balancingcompartment and the outlet passage; a by-pass port, establishingcommuniction between-the balancing compartment and the cushioningcompartment; and a valve controlling flow through said ports.

ALBERT. F. STUEBING.

